It’s too cold to fall asleep counting these sheep
Two people are sitting in the dirt beside the road staring at the mountain across the river. Several drivers slow down briefly and stare too. A Border Patrol agent stops to ask what they are looking at. It’s a cold day in late October as Annemarie Prince, a district wildlife biologist out of the Washington Department of Fish and Wildlife (WDFW) Colville office, and assistant wildlife biologist Ben Turnock search the peaks and plains of a mountain near the Canadian border for bighorn sheep from the Vulcan Mountain herd.
Mount Vulcan rises up across the highway — a jumble of extreme inclines with a few flat or rolling spaces. It’s lower to mid elevation is dotted with cows that the naked eye can easily pick out. But even with binoculars or a spotting scope it is difficult for the untrained eye to pick out a blur of movement or the white rumps of bighorn sheep that contrast with the greenish-brown backdrop.
“We see them all the time,” one resident, taking a walk with a companion, says. “One day they were down by the road and it was pretty cool.”
Most of the time though, these sheep hang out where you have to work to see them. They are known for living in foothill country near cliffs and bluffs. Their split hooves help with balance and rough hoof bottoms allow them to move easily across rugged terrain. Male bighorns — rams — have large horns that curl back over their ears and spiral up past their cheeks. Large rams can weigh over 250 pounds, with the horns alone weighing 30 pounds. Horn size can be a symbol of dominance among rams and indicate the bighorn’s age. A ram’s horns won’t have a full curl until they are seven or eight years old.
Female bighorns — ewes — are smaller and their horns average 9 to 12 inches with a slight curve backwards. Bighorns less than one year of age are referred to as lambs and stay with their mothers for the first year of their life to learn their home range.
WDFW formally manages17 bighorn sheep herds across central and eastern portions of Washington. Department staff count them each year to get an idea of how bighorn populations are doing. At last count, the Vulcan Mountain herd had around a minimum of 50 sheep in it. That’s an estimate because you can’t just walk up to a herd to count them. Instead, biologists rely on long distance counts, stopping at five pre-determined vantage points on a highway adjacent to the mountain to search the rock face with binoculars or spotting scopes. On this day, the first two stops don’t yield any sheep sightings, but the third stop is more productive.
“There’s some,” Prince says, pointing about halfway up the mountain. “Down from those two trees, just above where the powerlines are in your line of sight, moving across that open area are three rams- and there’s a fourth.”
Prince rattles off descriptions of each animal, and others that come out of the trees as she watches, while Turnock transcribes her inventory onto a form specifically for bighorn sheep counts.
“One ram, one half-curl, one three-quarter curl, two lambs…”
The next stop takes them up an icy mountain road, where they know of a good vantage point that provides a view directly across the valley to the upper areas of Vulcan Mountain, which are covered in snow. No sheep are spotted there either, but the reward for trekking up the mountain is a breathtaking spot to eat lunch while “glassing” the opposite mountain with binoculars.
While the late fall and early winter weather can make the count process a chilly one, Prince explains that they count the sheep every October and November to coincide with the bighorn breeding season — called the rut — which generally peaks in early November.
“This time of year, the males are mixed in with the ewes and lambs,” she said. “You can usually see bigger groups. The rest of the year the males are off in their bachelor groups and the herd is harder to count as a whole.”
Following the rut, lambs generally arrive between early April and June.
The next step in the counting process is a little more technical. Prince and Turnock head back down the mountain to another good vantage spot where Turnock sets up telemetry equipment to try to locate sheep that have been fitted with GPS tracking collars. To help control the size of central Washington’s Cleman Mountain herd and keep it from interacting with domestic sheep, eight sheep were transplanted from the Cleman herd in 2017, collared and released in the Vulcan Mountain area. This also bolstered the Vulcan Mountain herd and increased genetic diversity of the herd. The collared transplants help Prince and Turnock locate the herd during population surveys, using signals from their collars.
“There’s one over there,” Turnock says, listening to what- to the average person- sounds like static and beeping, and pointing north, “but I can’t see it. There’s also one over there.”
On this day, Turnock not only picks up a signal from the two collared sheep but also gets a mortality signal, meaning a collared bighorn has died. Now it’s his job to get coordinates from the collar and recover it from the steep terrain. He’s not daunted though– it’s unlikely to be as hard to recover as the time he located a collar in a golden eagle nest.
A few more sheep are counted, but this turns out to be a light day for Prince and Turnock, as they only observe about twelve bighorns total traversing the steep hillside. They aren’t worried by the low number of animals they saw this day. This is just one count in a series and other members of the herd are likely to turn up in later count efforts. This herd is co-managed with the Confederated Tribes of the Colville Reservation, so Prince and Turnock coordinate with tribal biologists who also count annually — typically from helicopters.
“They share data with us and vice versa,” says Prince. “It gives both of us a more complete picture of what is happening with the herd.”
And the helicopter counts mean less time Prince and Turnock spend sitting in frigid temperatures to count the animals.
There are about 1,380 bighorn sheep in 17 herds across the state. WDFW staff count them annually to assess the health of the herds. More information on bighorn sheep herds in Washington state, their habitat, and conservation of this species is on the WDFW website.